• 한국식품영양과학회지
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• 제23권3호
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• pp.387-395
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• 1994

The effect of vitamin C on th egramoxone toxicity in the duodenal globlet cells of rats were investigated suing histochemical methods. Rats in control, gramoxone and gramoxone+vitmain C (Vt.C) group, aged 6 to 7 weeks, were fed 18% casein diet. In th egramoxone group, neutral and acid mucins of the globlet cells in villi and crypts of duodenum tended to decrease as compared with the control group. And the globle cells secreting nonsuphated mucins tended to increase in number, being usually accompanied by a decrease of the globlet cells secreting suphated mucins which are prominent in the duodenal mucosa of control group. However, the goblet cells secreting nonsuphated mucins tended to increase in the gramoxone + Vt.C group. Morphological changes of the globlet cells in the gramoxone group were noted vacuolation and demolition of globlet cells, while those changes were not significant in the gramoxone +Vt. C group. It seems to be that Vt. C has alleviating effects on the gramoxone toxicity in secretion and production of the duodenal goblet cells.

• 한국미생물·생명공학회지
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• 제50권3호
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• pp.387-394
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• 2022

Verotoxin-1 (VT-1) or Shiga-like toxin 1 (Stx-1) is produced by enterohemorrhagic Escherichia coli (EHEC) and is an AB5 holotoxin with a strong inhibitor of protein synthesis. VT-1 is a type 2 ribosome-inactivating protein (RIP) that has been shown to have cytotoxic and anticancer potential by inducing necrosis, apoptosis, and cell cycle arrest, making it a promising antitumor candidate. Here, we tested the cytotoxicity of VT-1 on CaCo2 and NCM425 cell lines and the results showed that VT-1 was more potent on CaCo2. Morphological changes were also evaluated on the cellular level and the results showed that VT-1 caused a decrease in viable cell count, altered cell membrane permeability, and an increase in total nuclear intensity. On the other hand, VT-1 displayed a lesser impact on mitochondrial membrane potential (MMP) and cytochrome c release. On the expression of caspases 3 and 9, VT-1 exhibited an insignificant effect on both which alongside the mitochondrial membrane potential (MMP) and cytochrome c results, might indicate that CaCo2 suffered from the necrosis process as a mechanism of cell death after exposure to VT-1.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제54권6호
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• pp.274-278
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• 2005

Voltage transformer(VT) comparison measurement system is usually used for measurements of ratio error and phase angle error of VT made in industry. Both ratio error and phase angle error in VT are critically influenced by values of burden of VT used. External burden effects on both ratio error and phase angle error in VT are theoretically calculated. From the theoretical calculation, a method of evaluation for linearity of ratio error and phase angle error in VT measurement system have been developed using the standard capacitive burdens, with negligible dissipation factor less than 10$^{-4}$. These burden consists of five standard capacitors, with nominal capacitance of 1.1 $\mu$F, 1 $\mu$F, 0.1 $\mu$F, 0.01 $\mu$F, 0.001 $\mu$F. The developed method has been applied in VT measurement system of industry, showing in good consistency and linearity within 0.001 $\%$ between theoretical and measured values.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제50권4호
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• pp.197-203
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• 2001

Recently, the construction of gas insulated substation(GIS)s has been increased in Korea. But, the whole quantity of the VTs which were used in GIS has been imported. Under the circumstance that $SF_6$ gas power apparatus are being developed up to 800kV rating in Korea, the development of EＨＶ　$SF_6$ gas VT is essential for localizing the power apparatus. As for EHV VT, destructive ferroresonance can be generated due to the combination of capacitiances between poles of circuit breaker, ground capacitance of bus and nonlinear excitation property of VT core. But the theoretical analysis about ferroresonance has not been fully achieved in Korea. Therefore, in this paper the authors would like to contribute for localizing EHV $SF_6$ gas VT by developing the diagram of ferroresonance zone according to the parameters of the circuit and the saturable reactor.

• 동아시아식생활학회지
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• 제16권2호
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• pp.145-155
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• 2006

This study investigated the correlation of the nutritional status of antioxidant vitamins and serum lipids and MDA levels in postmenopausal women. Data about general characteristics, dietary intakes and biochemical parameters, including serum lipids, MDA and antioxidant vitamins levels, were collected from 85 postmenopausal women. The subjects were classified into three groups according to their serum total cholesterol level: normocholesterolemia group (NC, < 200 mg/dL), moderate hypercholesterolemia group (MC, $200{\sim}239mg/dL$) and hypercholesterolemia group(HC, ${\geq}240mg/dL$). The results are as follows. 1) General characteristics and serum MDA levels were not significantly different among the three groups. 2) Daily nutrients intakes adjusted to energy intake were not significantly different among the three groups, and were compatible with dietary reference intakes (DRIs) for Koreans. 3) Dietary Vt. A, ${\beta}-carotene$, Vt. C and Vt. E intake were not significantly different among the groups, while Vt. E intake was positively related with serum TC (r=0.288, p<0.05) and triglyceride (r=0.341, p<0.001) levels. 4) Serum Vt. A level standardized by serum TC level was significantly low and serum Vt. E level was significantly high in the HC group. Serum Vt. E level was positively related with serum TC level (r=0.389, p<0.001). 5) Dietary Vt. E intake was negatively correlated to serum MDA level (r=-0.242 p<0.05). Serum Vt. C and Vt. E levels were also negatively correlated to serum MDA level (r=-0.312, p<0.001 and r=-0.299, p<0.05). When the correlation was analyzed only in the group with hypercholesterolemia, correlation coefficients between the antioxidant vitamin and serum MDA level were higher. We concluded that intakes of antioxidant vitamins can contribute to decreasing the risk of cardiovascular disease by decreasing the oxidative stress of body rather than by controlling serum lipid levels.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제53권9호
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• pp.470-474
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• 2004

Both ratio error and phase angle error in voltage transformer(VT) depend on values of burden of VT used. A method of evaluation for linearity of ratio error and phase angle error in VT measurement equipment have been developed using the standard resistance burdens, with negligible AC-DC resistance difference less than $10^-6$. These burden consists of five standard resistors, with nominal resistance of 100 $\Omega$, 1 k$\Omega$, 10 k$\Omega$, 100 k$\Omega$, and 1 M$\Omega$. The developed method has been applied in VT measurement equipment of industry and the validity of the developed method has been verified by showing the consistency of the result of linearity obtained using VT with wide ratio error.

• 한국식품영양과학회지
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• 제38권1호
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• pp.47-51
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• 2009

비타민 C 섭취 및 요가가 중년 여성의 총항산화능, 지질과 산화 및 혈중지질에 미치는 영향을 알아보기 위하여 B광역시 H구에 거주하는 중년여성을 대상으로 12주간 실험을 실시하였다. 요가 프로그램은 주 3회, 1일 60분, 운동 강도 RPE $13{\sim}15$로 실시하였다. 비타민 C는 1일 1 g을 섭취시켰다. 12주 후 총항산화능의 변화는 정상군 28.23%, 비타민 C군 30%, 요가군 26.58%, 비타민 C 섭취와 요가군은 43.66%가 증가하였으나 군간 유의적인 차이가 없었다. 지질과산화물가의 변화는 정상군 10%, 비타민 C군 -25%, 요가군은 -32.14%, 비타민 C 섭취와 요가군은 -33.87%로 정상군에 비해 프로그램군이 유의적으로 감소하였으나 프로그램군간의 유의적인 차이는 없었다. 혈중지질농도 변화는 모든군에서 유의적인 차이가 없어 요가 또는 비타민 C 섭취에 따른 지질개선효과를 관찰할 수 없었다. 이상의 결과를 통해 중년여성에게 비타민 C 섭취나 규칙적인 요가 프로그램은 지질과산화물가를 낮춤으로써 체내 산화적 스트레스를 개선하는 효과가 있는 것으로 생각된다.

• 한국식품영양과학회지
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• 제22권6호
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• pp.823-832
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• 1993

This study was made to determine alleviating effects of vitamin C(Vt C) on the gramoxone toxicity in rats with respect to the growth gain, feed effeciency ratio, total lipid contents, lipid peroxication and protein patterns in rat liver. Growth gain, feed efficiency ratio and liver weight in the gramoxone group were decreased significantly as compared with the control group, while those values obtained in the gramoxone-Vt C group were increased as compared with the gramoxone group. Lipid contents and TBA value of rat liver of the gramoxone group were increased significantly as compared with the control group. However, those values of the gramoxone+Vt C group were decreased as compared with the gramoxone group. No significant differences were observed in the liver protein patterns between the gramoxone and the control group. The contents of liver protein were decreased significantly in the gramoxone group fed for 2 weeks as compared with the control group. The change of the liver protein patterns, such as the decrease of high molecular weight protein and the increase of low molecular weight protein were observed in the gramoxone+Vt C group.

• 항공우주기술
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• 제7권2호
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• pp.110-116
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• 2008

본 논문에서는 TVC 배터리의 설계 개념, 특성과 환경 및 성능 시험 결과에 대해 간략히 보인다 KSLV-I 상단에 탑재되는 TVC 배터리는 168개의 소니 18650VT 고전력 리튬이온 셀을 사용하며, 84개의 셀을 직렬로 구성한 후 각 열을 병렬로 2개 연결하여 추력 벡터제어(TVC) 시스템의 미션에 요구되는 전압(공칭 270V)과 전류를 공급한다. TVC 시스템의 부하 특성은 짧은 시간 동안 높은 전류 출력을 요구하는 펄스의 형태를 가진다. 무게를 최소화하며 시스템 요구 전력을 공급하기 위해 18650VT 셀을 적용하였다. 18650VT 셀은 고전력 응용분야를 위해 설계된 모델로 10C 연속 방전 능력을 갖고 있다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제54권11호
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• pp.503-507
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• 2005

Both ratio error and phase angle error in voltage transformer(VT) depend on values of VT burden used. Thus, precise measurement of burden is very important for the evaluation of VT. A method of evaluation for VT burden has been developed by employing the portable decade resistor, with AC-DC resistance difference less than 10-3. The burden value(value and power factor) can be obtained by conductance and susceptance, obtained by measuring the change of ratio error and phase angle error caused by the resistance change of decade resistor. The burden value and power factor obtained by the method are consistent with those obtained using power analyzer within corresponding uncertainties.